CFS, also known as Chronic Fatigue and Immune Dysfunction Syndrome (CFIDS) or Myalgic Encephalomyelitis (ME), is a disorder characterized by overwhelming chronic fatigue of greater than six months duration that is not improved by rest and may be worsened by physical or mental activity. Patients with CFS typically function at a significantly lower level of activity than they were capable of before the onset of illness.
CFS patients commonly report various symptoms including weakness, muscle pain, post-exertional fatigue lasting more than 24 hours, impaired memory and/or mental concentration, depression, and insomnia. These symptoms are often made worse by being tired and in pain the majority of one's waking hours. The immune system is frequently dysfunctional in patients experiencing chronic fatigue syndrome, and consequently many patients with CFS also experience frequent sore throats, colds, and flu-like symptoms. Benign lymphadenopathy can also occur in some patients. Other commonly observed symptoms of CFS include: abdominal pain, alcohol intolerance, bloating, chest pain, headaches, chronic cough, diarrhea, dizziness, dry eyes or mouth, ear aches, irregular heartbeat, jaw pain, morning stiffness, nausea, night sweats, psychological problems (depression, irritability, anxiety, and/or panic attacks), shortness of breath, skin sensations such as tingling, and weight loss.
The cause or causes of CFS have not been identified. CFS is a profoundly multifactorial condition. However, its myriad symptoms profile has been traced to a dis-integration of neurologic, endocrine, and immune system cooperation, possibly attenuated by dysfunction of the hypothalamic-pituitary-adrenal hormonal axis.
To be diagnosed with. CFS, patients typically satisfy two criteria: (1) significant to severe fatigue for at least six months (herein referred to as “chronic fatigue”), with other known medical conditions (whose manifestation can include fatigue) having been excluded by clinical diagnosis; and (2) concurrently four or more of the following symptoms: post-exertional malaise, impaired memory or concentration, unrefreshing sleep, muscle pain, multiple joint pains without redness or swelling, tender cervical or auxiliary lymph nodes, sore throat, and headache, such symptoms having persisted or recurred during six or more consecutive months of illness and not having predated the fatigue. It has been estimated that about 1% of the population in the United States has been diagnosed with CFS.
No prescription drugs have been developed specifically for CFS. The symptoms usually vary considerably over time and among patients. These factors can complicate the treatment process and typically require patients and health care professionals to constantly monitor and revise their treatment strategies. Current therapies for treating CFS primarily focus on attempts at relieving the most debilitating symptoms (i.e., pain, insomnia, and depression). Currently there are no United States Food and Drug Administration (“FDA”)-approved or generally accepted treatments that significantly improve or cure CFS.
Similarly, “fibromyalgia” is a condition that includes an overlapping list of symptoms with CFS and frequently includes fatigue, chronic musculoskeletal pain, chronic flu-like symptoms, depression, and cognitive dysfunction. Fibromyalgia is predominately characterized by widespread muscular pains and fatigue.
Fibromyalgia also is characterized by abnormal pain processing, sleep disturbance, chronic fatigue, and is often accompanied by significant psychological distress. Patients experiencing fibromyalgia may also have other symptoms, including morning stiffness, tingling or numbness in the hands and feet, headaches, including migraines, irritable bowel syndrome, problems with thinking and memory (sometimes called “brain fog”), painful menstrual periods, and other pain syndromes. The prevalence of fibromyalgia in the United States is estimated at 2%, affecting 5 million adults in 2005. The prevalence is much higher among women than men (3.4% versus 0.5%) (Female: Male ratio 7:1).
Lyrica (pregabalin capsules) is approved by the FDA for the treatment of fibromyalgia. Fibromyalgia also is commonly treated with a variety of drugs developed and approved for other purposes, such as analgesics, non-steroidal anti-inflammatory drugs (NSAIDS), antidepressants, tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), mixed reuptake inhibitors, and benzodiazepines.
Chronic fatigue may also be caused by other medical conditions. These include, among others, cancer, AIDS, chronic hepatitis B & C, autoimmune disorders, Lyme's disease, Parkinson's disease, Alzheimer's disease, psychological disorders including depression, attention deficit disorder (ADD), and attention deficit hyperactivity disorder (ADHD), multiple sclerosis, sickle cell anemia, and congestive heart failure. In the United States, 24% of the general population has had fatigue lasting 2 weeks or longer; 59%-64% of these persons report that their fatigue has no identifiable medical cause. In one study, 24% of patients in primary care clinics reported having prolonged fatigue (>1 month). In many persons with prolonged fatigue, the fatigue persists beyond 6 months and has no identifiable medical cause.
Accordingly, a significant need exists for compositions and methods for the treatment of chronic fatigue for patients suffering from CFS, fibromyalgia, chronic fatigue caused by or associated with dis-integration of the neuro-endocrine-immune axis, and chronic fatigue caused by other medical conditions. The present disclosure is intended to satisfy this need and is believed to provide significant advantages in patient health care where chronic fatigue is a major symptom.